The present invention relates generally to pumping systems, and more particularly to a suction chamber utilized with horizontal pumping systems.
It is well known that horizontal pumping systems are utilized in a variety of industries for a variety of different purposes. For example, in the oil and gas industry horizontal pumping systems are utilized to pump fluid, typically water that has been separated from oil to a selected destination, such as a tank or disposal well. Such pumping systems typically include a pump, a motor and a suction chamber positioned therebetween. A thrust bearing chamber is also generally included between the suction chamber and the motor. The fluid to be moved by the pump is drawn into the system through the suction chamber. The fluid is pumped through the discharge head of the pump, which may have a flexible hose or other pipe removably connected thereto. The fluid will pass through the hose and/or the connecting pipe into the tank or other desired reservoir.
The suction chamber includes a shaft sealing device which prevents fluid from leaking out the motor or thrust bearing chamber end of the suction chamber. Fluid leaks through the motor end of the suction chamber can contaminate the thrust bearing chamber and/or the motor and cause significant damage thereto. The sealing device in the suction chamber will wear over time, and therefore must be replaced periodically to prevent leakage. There are two types of sealing devices used in suction chambers, typically referred to as component seals and cartridge seals. Component seals are made up of a number of individual components, such as rings and adapters, snap rings and the seal element. To replace component seals, the pump is disconnected from the suction chamber, and each piece is removed individually. The procedure is therefore a delicate one which is time consuming and difficult, and requires considerable experience.
Cartridge seals, on the other hand, are preassembled seal assemblies that can be removed and replaced as an assembled unit.
The present method for replacing cartridge seals is to remove the cartridge seal from the motor or bearing end of the suction chamber. Typically, the thrust bearing chamber is disconnected from the pumping system and access is gained to the suction chamber through the motor end of the suction chamber. It is sometimes necessary to move the motor as well. Such a procedure is acceptable with respect to relatively short pumping systems and in situations where it is necessary or desired to remove the thrust bearing chamber. However, there are circumstances where it is desired to leave intact the motor, the bearing and any other equipment positioned on the motor side of the suction chamber.
For example, in some horizontal pumping systems, the motor may be a very large motor which may be mounted to a platform or other structure. A shaft extends horizontally from the motor and the bearing is supported at a particular height so as to prevent or at least to keep to a minimum any vibration experienced in the system. The suction chamber is connected in the pumping system forward of the thrust bearing chamber and the pump is connected to the suction chamber. The direction forward as referred to herein means the direction from the motor toward the pump and the direction backward is the opposite direction (i.e., from the pump to the motor). Whenever reference is made to the pump end or pump side of any piece of equipment it simply refers to the end or side of that piece of equipment closest to the pump. Likewise, reference to the motor end or motor side of a piece of equipment indicates reference to the end side of the equipment closest to the motor. The pump will typically be supported by a plurality of supports to keep the pump at a desired height. When the motor and/or the equipment between the motor and the suction chamber is disconnected, there is a likelihood that when that equipment is replaced and put back into service, it will be difficult to realign the motor and the thrust bearing chamber in such a way as to prevent vibration. In other words, by disconnecting and moving the thrust bearing chamber and/or the motor, it is likely that increased vibration will exist over what is desired. Thus there is a need for a method and apparatus which will provide for the replacement of cartridge seals in the suction chamber so as to prevent leakage from the suction chamber, which can be done without disturbing the equipment on the motor side of the suction chamber. There is likewise a need for a method and apparatus which will provide for replacement of the cartridge seal and which eliminates or at least alleviates the problem of increased vibration due to removal and attempted realignment of the motor and other equipment on the motor side of the suction chamber.
The present invention provides a suction chamber for use with a fluid pumping system and more particularly a suction chamber for use in a horizontal pumping system. The suction chamber is positioned between the motor and a pump in the horizontal pumping system. The pumping system may also include a thrust bearing chamber positioned between the motor and the suction chamber. The suction chamber has a pump end and a motor end and includes a housing. A cartridge seal assembly is disposed in the housing. A shaft extends from the thrust bearing chamber through the suction chamber and into the pump. The sealing assembly is disposed about the shaft in the suction chamber.
The suction chamber includes a removable end plate at the pump end thereof. The end plate along with the pump at the pump end of the suction chamber may be moved relative to the suction chamber so that access to the interior of the chamber can be gained through the pump end of the suction chamber. The sealing assembly is connected in the housing with a connecting means that is easily accessible from the pump end of the suction chamber. The connecting means may comprise fasteners extending through the pump side of the sealing assembly into the housing. The fasteners are easily accessible and removable from the pump end of the suction chamber.
Once access to the interior of the suction chamber has been gained through the pump end thereof, and the fasteners removed, the sealing assembly will simply slide off of the shaft. The removed sealing device can be replaced with a new sealing device that will prevent leaks through the motor end of the suction chamber. Once the new sealing device is in place, fasteners or other connecting means can be reinstalled and the pump can be reconnected to the pump end of the suction chamber. Once all the connections are made, the pumping system may be placed back in service and fluid can be drawn in through the suction chamber and delivered to the pump which will deliver the fluid to a desired location.
The present invention thus provides an apparatus and method for removing and replacing the sealing assembly of a suction chamber without disconnecting or disturbing the equipment positioned on the motor side of the suction chamber. By removing and replacing the sealing assembly through the pump end of the suction chamber, the motor and the thrust bearing chamber on the motor side of the suction chamber can be left intact and the risk of misalignment of the motor and thrust bearing chamber, which will cause undue and excessive vibration, is eliminated.